RU2643901C2 - Control device for automatic transmission - Google Patents

Abstract

FIELD: transportation.

SUBSTANCE: device comprises: a friction engagement element, an engagement start identification means, an identification prohibition means for prohibiting the identification by the engagement start identification means. The engagement start identification means is to identify that the friction engagement element has started the engagement. In case the electric motor load is increased by a predefined value, while controlling the number of revolutions, in which the number of the automatic transmission input shaft revolutions is controlled up to a predefined target number of revolutions, and when the motion range is selected, and the friction engagement element in the disengagement state is engaged. The identification prohibition means for prohibiting the identification by the engagement start identification means before identifying that the friction engagement element has started the engagement. In the event that a switching from the HEV-mode occurs, in which the driving forces from the engine and the electric motor are input to the input shaft, into the EV-mode, in which only the driving force of the electric motor is input to the input shaft.

EFFECT: error-free identification of the electric motor load variation, resulting from switching from the HEV-mode to the EV-mode.

5 cl, 10 dwg

Description

Technical field

[0001] The present invention relates to a control device for an automatic transmission into which driving forces from driving sources including a motor and an electric motor are input.

State of the art

[0002] Traditionally, a device is known in which an automatic transmission is contained in a drive circuit, and in which a point in time at which the load of the electric motor-generator, which controls the speed at a predetermined target number of revolutions, increases by a predetermined value, is defined as the moment the time at which the clutch engaged in the range of motion began engagement (see Patent Document 1).

[0003] In a conventional device, during a mode changeover from the HEV mode, in which the driving forces of the engine and the electric motor-generator are input to the input shaft of the automatic transmission, in the EV mode, in which only the driving force of the electric motor-generator is introduced into the automatic transmission, the engine shutdown process and the separation process between the engine and the electric motor generator (CL1 trip) are performed.

[0004] However, when switching from the HEV mode to the EV mode in which these processes are carried out, the load of the electric motor-generator during the speed control, at which the speed of the input shaft of the automatic transmission provides the target speed, varies independently from the engagement state of the clutch engaged in the range of motion. Therefore, when the above mode switching occurs prior to determining the start of the clutch engagement, the load variation of the electric motor-generator, which occurs due to the mode switching, is erroneously determined as the start of the clutch engagement. This is an object of the present invention.

Pre-Published Documents

Patent documents

[0005] Patent Document 1. Publication of a Patent Application (Japan) (Tokkai) 2009-190584.

Disclosure of invention

[0006] An object of the present invention is to provide a control device for an automatic transmission that does not erroneously detect a variation in electric motor load that occurs due to switching from the HEV mode to the EV mode as the engagement of the friction engagement element.

[0007] A control device for an automatic transmission according to the present invention is a control device for an automatic transmission into which driving forces are inputted from driving sources including an engine and an electric motor. The control device for automatic transmission includes: a friction engagement element engaged in a range of motion; means for determining the start of engagement; and a means of prohibiting determination.

The means for determining the start of engagement determines that the friction engagement element begins to engage if the electric motor load increases by a predetermined amount during the speed control at which the number of revolutions of the input shaft of the automatic transmission is controlled to a predetermined target number of revolutions, and when the range is selected movement, and the friction engagement element engages in a disengaged state.

The means of prohibiting determination prohibits the determination by means of determining the start of engagement before determining that the friction engagement element has started engagement, and in case there is a switch from the HEV mode, in which the driving forces of the motor and electric motor are input to the input shaft, in the EV mode, in which only the driving force of the electric motor is input to the input shaft.

[0008] Thus, until it is determined that the friction engagement element has started engagement, and if a mode switchover occurs from the HEV mode to the EV mode, the determination inhibiting means prohibits the determination of the engagement start by the determination means.

In other words, the means for determining the start of engagement determines that the friction engagement element starts engaging while controlling the number of revolutions of the input shaft of the automatic transmission, and if the load of the electric motor increases by a predetermined amount when the friction engagement element is engaged in the disengaged state, with a selected range movement.

However, in the event that the switching occurs from the HEV mode to the EV mode, the engine shutdown process and the separation process between the engine and the electric motor are performed so that the load of the electric motor varies.

Thus, in the case where a range of motion is selected and the friction engagement element engages, switching from the HEV mode to the EV mode intervenes. In this case, the variation of the load of the electric motor, formed due to the process of stopping the engine, etc., is erroneously determined as the variation of the load due to the start of engagement of the friction engagement element. Therefore, when a switchover occurs from the HEV mode to the EV mode, the determination of the start of engagement of the friction engagement element due to variation in the load of the electric motor is not performed.

Therefore, the erroneous determination of the variation in the load of the electric motor, which occurs due to the switching from the HEV mode to the EV mode, as the start of engagement of the friction engagement element, may not be allowed.

Brief Description of the Drawings

[0009] FIG. 1 is a view of an overall system configuration representing an FR-type hybrid vehicle (vehicle example) in a rear-wheel drive system to which an automatic transmission control device in the first preferred embodiment is applied.

FIG. 2 is a map view representing an EV-HEV selection card specified in an integrated controller mode selection section in a first preferred embodiment.

FIG. 3 is a schematic view representing one example of an automatic transmission that contains a friction engagement element that is a stroke recognition control object in an automatic transmission control device in a first preferred embodiment.

FIG. 4 is a gearing operation table representing an engagement state of each friction engagement member for each of the gear changes in an automatic transmission in the first embodiment.

FIG. 5 is a map view representing one example of an automatic transmission gear shift map defined in an AT controller in a first preferred embodiment.

FIG. 6 is a flowchart showing an operational sequence of an N → D selection control process performed in an AT controller in a first preferred embodiment.

FIG. 7 is a flowchart representing a flowchart of a process of setting the inhibition flags executed in the AT controller in the first preferred embodiment.

FIG. 8 is a timing chart representing each characteristic of phase, speed, input shaft torque, control torque CL1, actual torque CL1, adjustable hydraulic pressure CL1, timer, inhibit flag, and friction engagement element in case the shift from HEV- mode, the EV mode intervenes according to the N → D selection control when the hybrid vehicle in which the control device in the first embodiment is mounted is stopped.

FIG. 9 is a flowchart representing a flowchart of a prohibition flag setting process performed in an AT controller in a second preferred embodiment.

FIG. 10 is a flowchart representing a flowchart of a prohibition flag setting process performed in an AT controller in a third preferred embodiment.

Detailed Description of Embodiments

[0010] Optimum embodiments for implementing a control device for an automatic transmission according to the present invention are explained based on the first, second and third preferred embodiments shown in the drawings.

First Embodiment

[0011] First, the structure is explained.

The control device for automatic transmission in the first embodiment is explained with sectioning on the sections "General system configuration", "Detailed design of the automatic transmission", "Detailed structure of the selection process N → D" and "Detailed structure of the process of setting the prohibition flags".

[0012] General system configuration

FIG. 1 shows a FR-type hybrid rear-wheel drive vehicle to which an automatic transmission control device in the first embodiment is applied. FIG. 2 shows an example of an EV-HEV selection card defined in the mode selection section of the integrated controller 10. Hereinafter, a general system configuration based on FIG. 1 and 2.

[0013] An FR-type hybrid vehicle drive circuit as shown in FIG. 1, includes: Eng engine; first clutch CL1; electric motor / generator MG (electric motor); second clutch CL2; AT automatic transmission; input drive shaft IN; propeller shaft PS; differential DF; DSL left drive shaft; DSR right drive shaft; left rear wheel RL (drive wheel); and right rear wheel RR (drive wheel). It should be noted that M-O / P stands for mechanical oil pump, S-O / P stands for electric oil pump, FL stands for front left travel wheel, and FW stands for flywheel.

[0014] The first clutch CL1 is an engagement member disposed between the eng engine Eng and the electric motor / generator MG, and is a so-called normally closed clutch of the type in which the engagement state is generated by the bias force of the diaphragm spring and the like when hydraulic pressure CL1 is not applied, and the tripping state is generated by adding hydraulic pressure CL1 against this bias force.

[0015] An AT automatic transmission is a multi-stage transmission in which gear shifting stages of 7 forward speeds / 1 reverse speeds are automatically shifted according to vehicle speed, accelerator opening angle, etc.

The second clutch CL2 is located between the electric motor / generator MG and the left and right rear wheels RL, RR. As the second CL2 clutch, the addition of a special clutch independent of the automatic transmission is not used, but one friction engagement element (clutch or brake) is used to shift the AT automatic transmission. In other words, out of the plurality of friction engagement elements engaged at respective gearshift steps of the AT automatic transmission, one of the friction engagement elements, which is selected as the element that meets the engagement condition and the like, serves as the second clutch CL2. It should be noted that the first clutch hydraulic pressure control unit 6 and the second clutch hydraulic pressure control unit 8 are included in the AT hydraulic pressure control valve unit CVU, further installed in the AT automatic transmission.

[0016] This FR-type hybrid vehicle, as modes according to the difference in drive shape, includes: an electric vehicle mode (hereinafter, referred to as an "EV mode"); hybrid vehicle mode (hereinafter referred to as the "HEV mode"); and a driving torque control mode (hereinafter, referred to as a “WSC mode”).

[0017] The above "EV mode" is a mode in which the first clutch CL1 is disengaged, and the driving source is only an electric motor / generator MG, and includes a driving mode due to the electric motor (movement due to the power of the electric motor ) and the mode of generating electric power due to the generator (regeneration due to the generator). This EV mode is selected, for example, when the requested driving force is low and the battery SOC is provided.

[0018] The above "HEV mode" is a mode in which the first clutch CL1 is engaged and the driving sources are an Eng engine and an electric motor / generator MG, and includes: a driving mode using an electric motor ( movement due to electric motor power); electric power generation mode due to the engine (regeneration due to the generator); and a mode of generating regenerative power during deceleration (regeneration due to a generator). This "HEV mode" is selected, for example, when the requested driving force is high or when the battery SOC is insufficient.

[0019] The above "WSC mode" is a "HEV mode" in the form of a drive. However, the WSC mode is a mode in which the MG motor / generator is subject to such a speed control that, while the second clutch CL2 is maintained in the gear engaging state in the sliding mode, the overload capacity for transmitting the torque of the second couplings CL2. The torque transfer power of the second clutch CL2 is controlled in such a way that the driving force transmitted through the second clutch CL2 becomes the requested driving force arising in the driver's control variable of the accelerator pedal. This “WSC mode” is selected in the region in which the engine speed is lower than the idle speed in such a case in which the vehicle starts driving in the “HEV mode” selection state.

[0020] An FR-type hybrid vehicle control system as shown in FIG. 1 includes: a motor controller 1; controller 2 of the electric motor; inverter 3; battery 4; controller 5 of the first coupling; node 6 regulating the hydraulic pressure of the first coupling; AT controller 7; node 8 for regulating the hydraulic pressure of the second coupling; brake controller 9; and integrated controller 10.

[0021] Each controller 1, 2, 5, 7, 9 and the integrated controller 10 are connected via a CAN communication line 11 through which mutual exchange of information is possible. It should be noted that the reference number 12 indicates the engine speed sensor, the reference number 13 indicates the circular position sensor, the reference number 15 indicates the first clutch stroke sensor, which determines the piston stroke position 14a of the actuator 14 based on the hydraulic pressure, the reference number 19 denotes a wheel speed sensor, and reference number 20 denotes a brake stroke sensor.

[0022] The AT controller 7 inputs information from the accelerator opening angle sensor 16, the vehicle speed sensor 17, the driving mode switch 18 determining the position of the selected range (N-band, D-band, R-band, P-band, etc. d.). Then, in the course of driving with the selected D-range, the optimal gearshift stage is detected from the position of the driving point determined according to the APO opening angle of the accelerator and the vehicle speed VSP present on the gearshift map (see Fig. 5), and the control command in order to reach the desired gear shift stage, it is output to the hydraulic pressure control valve assembly ATU AT. In addition to this gear shift control, the AT controller 7 performs gear / slip / disengage control for the first clutch CL1 and the second clutch CL2 based on instructions from the integrated controller 10.

[0023] The integrated controller 10 controls the energy consumption of the entire vehicle and serves to ensure the most efficient operation of the vehicle. The integrated controller 10 inputs the required information from the sensor 21 of the number of revolutions of the electric motor, which determines the number Nm of revolutions of the electric motor, and other sensors and switches 22 and information through the line 11 CAN-communication. This integrated controller 10 includes a mode selection section that selects a desired mode from a position at which a driving point determined according to an accelerator opening angle APO and a vehicle VSP speed is present on the EV-HEV selection map shown in FIG. 2 as the target mode. Further, when the mode is switched from the "EV mode" to the "HEV mode", engine start control is performed. In addition, when the mode is switched from "HEV mode" to "EV mode", engine shutdown control is performed. With this engine stop control, a disengagement process CL1 is performed in which a hydraulic pressure CL1 is applied to the first clutch CL1 engaged in the “HEV mode” and an engine shutdown process in which the separated engine Eng is stopped due to the disengagement of the first clutch CL1.

[0024] Detailed design of an automatic transmission

FIG. 3 shows a schematic view of an example of an AT automatic transmission in a first preferred embodiment.

FIG. 4 shows the engagement states of respective friction engagement elements for respective gearshift stages in an AT automatic transmission.

FIG. 5 shows an example of an AT automatic transmission gearmap set in the AT controller 7.

A detailed structure of an AT automatic transmission is explained based on FIG. 3-5.

[0025] The AT automatic transmission is a multi-stage transmission with 7 forward speeds and 1 reverse speed. As shown in FIG. 3, a driving force from at least one of an eng engine Eng and an electric motor / generator MG is input from an input transmission shaft Input, and a gear change mechanism having four planetary gears and seven friction engagement elements performs gear shifting for the rotational speed, and the switched speed is output from the output transmission shaft Output.

[0026] As a gear shifting mechanism, a first planetary gear set GS1 including a first planetary gear G1 and a second planetary gear G2, and a second planetary gear set GS2 including a third planetary gear G3 and a fourth planetary gear G4 gears are coaxially placed in this sequence.

As the hydraulic pressure-driven friction engagement elements, a first clutch C1, a second clutch C2, a third clutch C3, a first brake B1, a second brake B2, a third brake B3 and a fourth brake B4 are arranged. In addition, as the gearing elements driven by the mechanical drive, a first one-way clutch F1 and a second one-way clutch F2 are arranged.

[0027] Each of the first planetary gear G1, the second planetary gear G2, the third planetary gear G3 and the fourth planetary gear G4 is a planetary gear with the same type of gears having a sun gear (S1-S4), a ring gear ( R1-R4) and the carrier (PC1-PC4) supporting the satellites (P1-P4) engaged with both gears (S1-S4) and (R1-R4).

[0028] The input transmission input shaft is coupled to the second ring gear R2 to introduce a rotational driving force from at least one of the engine Eng and the electric motor / generator MG. The output transmission output shaft is coupled to the third carrier PC3 and transmits the output rotational driving force to the driving wheels (left and right rear driving wheels RL, RR) through the main gear, etc.

[0029] The first ring gear R1, the second carrier PC2 and the fourth ring gear R4 are inseparably engaged by the first link member M1. The third ring gear R3 and the fourth carrier PC4 are inseparably engaged by the second link member M2. The first sun gear S1 and the second sun gear S2 are inseparably engaged by the third link member M3.

[0030] FIG. 4 shows a table of meshing operations. In FIG. 4, the O mark indicates that the corresponding friction engagement element engages under the influence of hydraulic pressure in the driving state, the (O) mark indicates that the corresponding friction engagement element engages under the influence of hydraulic pressure in the inertia state (in the state of movement, a one-way clutch is working), and the absence of a mark indicates that the corresponding friction engagement element is in the disengaged state.

[0031] By performing such a replacement gear shift, in which of the corresponding friction engagement elements, one friction engagement element that is engaged is engaged and another friction engagement element that is engaged is engaged, a gear shift stage of 7 forward gears can be realized and 1 reverse gear, as shown in FIG. 4. In addition, when during the stopping of the vehicle, the selection operation N → D, in which the range is switched from the neutral range (N-range) to the driving range (D-range), which is the range of motion, elimination control is performed the free travel of the second brake B2 (friction engagement element engaged in the range of motion). It should be noted that the free-wheeling control is a control in which an initial hydraulic pressure is applied in order to eliminate the clearance (free-wheeling) of the brake disk of the second brake B2. This freewheel removal control is performed in order to provide a response response at the beginning of the vehicle’s movement, in the state of immediate engagement under the influence of the hydraulic pressure of the second brake B2, during the start of movement by the operation of depressing the accelerator pedal. It should be noted that during the start of the vehicle movement using the selection operation N → D, the “first speed step” is obtained by engaging the second brake B2 and engaging the one-way clutch F1 and the second one-way clutch F2. In this case, the second brake B2 serves as the second clutch CL2.

[0032] FIG. 5 shows a gearshift map. When the driving point on the map, indicated by the vehicle speed VSP and the accelerator opening angle APO, crosses the upshift gear shift line, the upshift gear shift command is output. For example, when the gear shift stage is the first speed step, and the driving point (VSP, APO) crosses the gear shift line “up” 1 → 2, a gear shift command “up” 1 → 2 is output. It should be noted that FIG. 5 describes only the upshift gearshift lines, but, of course, the downshift gearshift lines are defined with hysteresis for each of the individual upshift gearshift lines.

[0033] Detailed structure of the selection process N → D

FIG. 6 shows a flowchart representing an operational sequence of an N → D selection control process performed in the AT controller 7 in the first preferred embodiment. Hereinafter, each step in FIG. 6, representing the detailed structure of the selection control process N → D.

[0034] In step S1, the AT controller 7 determines whether or not the signal from the drive mode switch 18 indicates that the range is switched from the N-band to the D-band, namely, that N → D selection control is performed. If “Yes” (selection control N → D is executed), the procedure proceeds to step S2. If “No” (without controlling the selection N → D), the procedure proceeds to return.

[0035] In step S2, the AT controller 7 determines whether or not the inhibit flag 1 is equal, after determining in step S1 that selection control N → D is performed. If “Yes” (prohibition flag = 1), the procedure proceeds to step S5. If “No” (prohibition flag = 0), the procedure proceeds to step S3.

It should be noted that the “prohibition flag” is a flag that prohibits the determination of the start of engagement, determining that the piston stroke is completed, and the engagement of the second brake B2 starts when the condition is established that “the magnitude of the variation of torque MG> threshold value", while selecting N → D in HEV mode. In other words, the determination of the completion of the stroke (means of determining the start of engagement), performed by setting the condition that "the magnitude of the variation of torque MG> threshold value", is the determination of the start of engagement of the second brake B2, which begins to transmit the driving torque through the second brake B2.

[0036] In step S3, the AT controller 7 performs normal selection control N → D after determining in step S2 that the prohibition flag = 0, and the procedure proceeds to step S4.

It should be noted that the “normal N → D selection control” is the free-wheeling elimination control of the second brake B2 by means of an adjustable hydraulic pressure, which is overwritten and stored through the recognition control during the N → D selection.

[0037] In step S4, after the normal selection control N → D in step S3, a stroke recognition control is enabled at which the adjustable hydraulic pressure of the second brake B2 is recognized and the procedure proceeds to return.

It should be noted here that the “stroke recognition control” is a control in which the adjustable hydraulic pressure of the second brake B2 is recognized, so that the time for controlling the removal of the free play from the start of the selection N → D to the end of the stroke is the target time. In other words, the required time is measured from the start of the selection N → D to the completion of the piston stroke, and the adjustable hydraulic pressure is increased by a predetermined recognizable value if the required time exceeds the target time. Conversely, if the required time is less than the target time, the adjustable hydraulic pressure is reduced by a predetermined recognizable value. Recognition control is a control in which the required time from the start of the selection N → D to the completion of the piston stroke converges to the target time by subjecting such a correction many times with recognition, as described above, regardless of dispersion, deterioration due to wear, etc. .

In addition, it should be noted that the “tolerance of control with stroke recognition” is as follows: The determination of the end of the piston stroke (= start of engagement) is made when the condition is established that “the magnitude of the variation of torque MG> threshold value” during selection N → D in HEV mode, and the required time is measured from the start of the selection N → D to the completion of the piston stroke. Recognition control is then enabled, which corrects the adjustable hydraulic pressure during the freewheel removal control, depending on whether the desired target time is longer or shorter.

[0038] In step S5, after determining in step S2 that the inhibit flag = 1, open-loop control is performed by selecting N → D, and the procedure proceeds to step S6 (hydraulic pressure setting means during inhibit).

It should be noted here that “open-loop control by selecting N → D” is a control (open-loop control) (means of denying determination), in which case, if the prohibition flag, which prohibits determining the start of engagement, is 1, adjustable hydraulic the pressure by which the free play is eliminated for the second brake B2 (= CL2) is an adjustable hydraulic pressure that exceeds the usual adjustable hydraulic pressure (recognizable hydraulic pressure), which is not prohibited for a predetermined time interval by means of an overrun timer.

[0039] In step S6, after the open-loop control by selecting N → D in step S5, the stroke recognition control is disabled at which the adjustable hydraulic pressure is detected during the freewheel removal control for the second brake B2, and the procedure proceeds to return.

It should be noted here that the “prohibition of determining the start of engagement” is the prohibition of determining the end of the piston stroke (= start of engagement) when the condition is established that the “magnitude of the variation of torque MG> threshold value” during the selection of N → D in HEV- mode, and control with stroke recognition is not performed. It should be noted that when control with stroke recognition is disabled, the end of the freewheel removal control is determined from the expiration of the freewheel removal timer.

[0040] Detailed structure of the prohibition flag setting process

FIG. 7 shows a flowchart representing a flowchart of a prohibition flag setting process performed in the AT controller 7 in the first preferred embodiment. Each step in FIG. 7, representing a detailed structure of the prohibition flag setting process.

[0041] In step S11, the AT controller 7 determines whether or not 0 is the previous value of the adjustable hydraulic pressure CL1 for the first sleeve CL1 (previous value of the adjustable hydraulic pressure CL1 = 0). If “Yes” (previous adjustable hydraulic pressure CL1 = 0), the procedure proceeds to step S12. If “No” (previous adjustable hydraulic pressure CL1 ≠ 0), the procedure proceeds to step S14.

[0042] In step S12, the AT controller 7 determines whether or not the adjustable hydraulic pressure CL1 exceeds a threshold value, after determining in step S11 that the previous value of the adjustable hydraulic pressure CL1 = 0. If “Yes” (“adjustable hydraulic pressure CL1> threshold value "), the procedure proceeds to step S13. If “No” (“adjustable hydraulic pressure CL1 ≤ threshold value”), the procedure proceeds to step S14. It should be noted that the “threshold value” is set equal to the value of the adjustable hydraulic pressure, which provides a hydraulic pressure equivalent to the disengagement of the first normally closed type clutch CL1.

[0043] In step S13, the AT controller 7 sets the countdown timer to a predetermined value after determining in step S12 that “the adjustable hydraulic pressure CL1 is a threshold value”, and the procedure proceeds to step S14.

It should be noted that a predetermined value is set based on the time required to determine that the Eng engine is not in full combustion mode during the engine shutdown control, performed in addition to switching the mode from the HEV mode to the EV mode.

[0044] In step S14, the AT controller 7 updates the previous value of the adjustable hydraulic pressure CL1 after determining in step S11 that the adjustable hydraulic pressure CL1 ≠ 0, after determining in step S12 that "the adjustable hydraulic pressure CL1 ≤ threshold value" , or after determining in step S13 that the countdown timer is set, and the procedure proceeds to step S15. It should be noted that the previous value of the adjustable hydraulic pressure CL1 is updated as follows.

Previous value of adjustable hydraulic pressure CL1 = current value of adjustable hydraulic pressure CL1.

[0045] In step S15, the AT controller 7 determines whether or not the timer value set in step S13 is a timer value> 0 after updating the previous controlled hydraulic pressure value CL1 in step S14.

If “Yes” (timer value> 0), the procedure proceeds to step S16. If “No” (timer value = 0), the procedure proceeds to step S18.

[0046] In step S16, the AT controller 7 sets a prohibition flag representing the prohibition of determining the start of engagement to be 1 after determining in step S15 that the timer value is> 0, and the procedure proceeds to step S17. It should be noted that the “prohibition flag” is the flag used in step S2 of FIG. 6, which prohibits the determination of the start of engagement, determining that the piston stroke is completed, and the engagement of the second brake B2 starts when it is set that “ torque variation MG> threshold value "during selection of N → D in HEV mode.

[0047] In step S17, the AT controller 7 counts the timer in the reverse order, wherein the timer value decreases for that of the process periods after the prohibition flag is set in step S16, and the procedure proceeds to return.

[0048] In step S18, the AT controller 7 resets the prohibition flag representing the prohibition of determining the start of engagement (prohibition flag = 0), after determining in step S15 that the timer value = 0, and the procedure proceeds to return.

[0049] The following explains the sequence of operations.

The sequence of operations for the control unit for automatic transmission AT in the first preferred embodiment is explained with sectionalization of the explanations into the sections "The sequence of operations in the process of controlling the selection N → D", "The sequence of operations in the process of setting the prohibition flags" and "The sequence of operations when intervening in changing the mode during the selection control N → D ".

[0050] The sequence of operations in the process of selection control N → D

During the selection control N → D, which engages the second brake B2, the control of switching from the HEV mode to the EV mode is intervened, so that the corresponding controls mutually overlap and are executed. At this time, it is necessary to prohibit the determination of the start of engagement according to the constant condition, since the determination of the start of engagement is erroneously determined. The rest of this document explains the flow of operations in the N → D selection management process, which addresses this issue.

[0051] When N → D selection control is performed, and the prohibition flag is 0, the flow of steps through “step S1 → step S2 → step S3 → step S4 → return” shown in FIG. 6. In step S3, the normal N → D selection control is performed, in which the free-wheeling removal control for the second brake B2 is performed according to the adjustable hydraulic pressure overwritten and stored by the recognition control during the N → D selection.

In step S4, stroke recognition control is enabled in order to recognize the adjustable hydraulic pressure of the second brake B2.

[0052] Therefore, when the N → D selection control is performed in the HEV mode, and the prohibition flag = 0, the completion of the piston stroke is determined when the condition is set that “the magnitude of the torque variation MG> threshold value”, and the required time is measured ( clearance control time) from the moment the selection N → D begins, until the end of the piston stroke. Then, the adjustable hydraulic pressure during the override elimination control is corrected with recognition depending on whether the required time of the target time is longer or shorter.

[0053] On the other hand, when N → D selection control is performed, and the prohibition flag is 1 in the flowchart of FIG. 6, the process is repeated in the form of “step S1 → step S2 → step S5 → step S6 → return”. In step S5, the open-loop control is performed by selecting N → D, in which the adjustable hydraulic pressure that eliminates the free play for the second brake B2 (= CL2) is higher than the usual adjustable hydraulic pressure (recognized hydraulic pressure). In step S6, a stroke recognition control is prohibited at which an adjustable hydraulic pressure is detected during the free-wheeling removal control of the second brake B2.

[0054] Therefore, when the selection control N → D is performed, and the prohibition flag = 1, it is prohibited to determine that the piston stroke is completed when the condition is set that “the magnitude of the torque variation MG> threshold value” during the selection of N → D in HEV mode.

[0055] As described above, in the first preferred embodiment, in the event that a switchover occurs from the HEV mode to the EV mode, and until it is determined that the second brake B2 has started engagement, it is prohibited to determine the start of engagement according to the condition that " torque variation value MG> threshold value ".

[0056] In other words, the electric motor / generator MG is subjected to such a speed control that the input speed of the AT automatic transmission becomes constant during the HEV mode (WSC mode) while the vehicle is stopped. When, at this time, the engagement of the second brake B2 begins, the load applied to the motor / generator MG increases. However, the torque of the MG motor / generator is increased so that the speed control is maintained so that the input speed is constant regardless of the increase in this load. Therefore, when the load of the electric motor / generator MG increases by a predetermined amount, and a condition such that “torque variation value MG> threshold value” is set, it can be determined that the piston stroke is completed and the second brake B2 has started engagement.

[0057] However, when a switchover occurs from the HEV mode to the EV mode, an engine shutdown process and a separation process between the Eng engine and the electric motor / generator MG are performed. Thus, the load of the motor / generator MG varies regardless of the start of engagement of the second brake B2. Therefore, when the freewheel removal control for the second brake B2 is performed in response to the start of the selection N → D, the switching from the HEV mode to the EV mode intervenes. In this case, the load variation of the electric motor / generator MG, which occurs due to the process of stopping the engine, etc., is erroneously determined as the load variation due to the start of engagement of the second brake B2.

[0058] Therefore, when the mode switch from the HEV mode to the EV mode occurs during the N → D selection control and the inhibit flag is set to 1, the determination of the start of engagement for the second brake B2 due to the variation in the load of the motor / generator MG is not performed. Therefore, the erroneous determination of the load variation of the electric motor / generator MG, which is formed along with the switching of the mode from the HEV mode to the EV mode, as the start of engagement of the second brake B2, may not be allowed.

[0059] In the first preferred embodiment, when the prohibition flag = 1 during the selection control N → D, the procedure proceeds to step S5. In step S5, such an open-loop control is adapted by selecting N → D such that the adjustable hydraulic pressure of the second brake B2 is higher than the hydraulic pressure that is not disabled for a predetermined time interval by the overrun timer.

According to this structure described above, if the determination of the start of engagement for the second brake B2 is prohibited (inhibit flag = 1), the clearance control for the second brake B2 is completed at a time shorter than the target time during normal selection control N → D.

Therefore, even if the start of engagement of the second brake B2 cannot be determined from the magnitude of the load variation of the electric motor / generator MG, a state in which engagement of the second brake B2 begins (the state in which the free wheeling of the second brake B2 is completed) can be guaranteed.

[0060] The sequence of operations in the process of setting flags prohibition

As described above, when switching from the HEV mode to the EV mode occurs, the prohibition flag is set to 1 due to a specific condition representing that a mode switching occurs. Hereinafter, the document explains the flow of operations in the process of setting the prohibition flags of the first embodiment using the disengagement condition of the first clutch CL1 as a specific condition representing a mode switch.

[0061] When the condition is established that the previous value of the adjustable hydraulic pressure CL1 = 0, and "adjustable hydraulic pressure CL1 (current value)> threshold value", based on the command to switch from HEV mode to EV mode in the flowchart the operations of the method of FIG. 7, the procedure is performed in the sequence “step S11 → step S12 → step S13 → step S14 → step S15 → step S16 → step S17 → step S17 → return”. In step S13, the countdown timer is set to a predetermined value. In step S16, after determining in step S15 that the timer value is> 0, the prohibition flag representing the prohibition of determining the start of engagement is set to 1.

[0062] Then, until the timer value becomes 0 from the subsequent control period, in the flowchart of FIG. 7, the sequence of operations is repeated in the form “step S11 → step S14 → step S15 → step S16 → step S17 → return”, so that the prohibition flag is maintained = 1. In addition, when the timer value = 0, in the flowchart of the method FIG. 7, the process is repeated in the form of “step S11 → step S14 → step S15 → step S18 → return”. In step S18, the prohibition flag is reset to 0 (prohibition flag = 0).

[0063] In a first preferred embodiment, a structure is adapted such that if the first clutch CL1 starts disengaging before determining that the second brake B2 has started engagement, the prohibition flag prohibiting the determination of the engagement start is set to 1 (prohibition flag = one).

In other words, when switching from the HEV mode to the EV mode is performed, the clutch disengagement control is started, at which the first clutch CL1 located between the engine Eng and the electric motor / generator MG is disengaged. Therefore, by prohibiting the determination of the start of engagement when the first clutch CL1 has started disengaging, a variation in the load of the motor / generator MG, which is formed when erroneous determination of switching from the HEV mode to the EV mode as the start of engagement can be prevented.

[0064] The sequence of operations when interfering with the change of mode during the control selection N → D

FIG. 8 shows a timing chart representing each characteristic in the event that switching from the HEV mode to the EV mode interferes with the N → D selection control in the event that the hybrid vehicle in which the control device is mounted in the first preferred embodiment is stopped. Later in this document, the sequence of operations when intervening in a mode change during the N → D selection control.

[0065] In the timing diagram of FIG. 8, t1 denotes the time at which the selection control N → D begins in the template (1) in the HEV mode; t2 indicates the time at which the engine stop and CL1 trip are started based on the command to change the mode from HEV mode to EV mode; t3 denotes the time at which the transition through zero of the engine torque and the motor torque ends; t4 denotes the time at which the transition through zero revolutions begins for the engine speed and the motor speed; t5 denotes the time at which the transition through zero revolutions ends, and at which the EV mode begins.

[0066] Time t1 - time t2 is the phase of engine power generation in HEV mode. For example, when such a condition for completing the charge for the battery 4 at the time t2 is established, the phase transition signal from the HEV mode to the EV mode is output. In this phase, with the engine idle speed Eng as the target engine speed, the MG motor / generator is subject to such speed control to maintain the engine idle speed. The engine torque is controlled as the torque at which the required power is generated, and the electric motor torque is controlled as the negative torque (recovery torque), at which the engine torque is converted into energy to generate power. The control torque CL1 and the actual torque CL1 are the torque supporting engagement of the first clutch CL1. The adjustable hydraulic pressure CL1 is maintained at zero pressure. Since the first clutch CL1 is in the engaged state, the timer value and the inhibit flag are set to 0. The phase of engine power generation in HEV mode at time t1 - time t2 is the interval of time of normal control and recognition tolerance.

[0067] Time t2 - time t3 is a phase for phase (1) of the HEV → EV transition. At time t2, the engine shutdown process and the first clutch trip process begin. If, at time t3, the transition through zero of engine torque and electric motor torque is completed, the phase goes into the next phase. In this phase, after time t1 - time t2, with the engine idle speed Eng as the target engine speed, the speed control of the motor / generator MG is maintained in order to maintain the engine idle speed. The engine torque is controlled in such a way that the torque is gradually reduced due to throttle closing control, and the electric motor torque is controlled in such a way that the torque is gradually increased synchronously with the engine torque.

The adjustable torque CL1 and the actual torque CL1 are controlled so that the response of the actual torque CL1 is delayed relative to the adjustable torque CL1, but is controlled to decrease in the direction in which the first clutch CL1 is gradually disengaged. The adjustable hydraulic pressure CL1 rises step by step during t2 and then gradually rises in the time direction t3. The timer is set to a predetermined value when the timer exceeds a threshold value due to an increase in the adjustable hydraulic pressure CL1, and gradually decreases in the time direction t3. The inhibit flag is set to 1 (inhibit flag = 1) starting with a timer value> 0. Phase (1) of the HEV → EV transition for time t2 - time t3 provides an open-loop control time interval and recognition inhibit.

[0068] Time t3 - time t4 is the phase (2) of the transition HEV → EV. When the zero transition of the engine torque and the electric motor torque is completed at time t3, the continuation of the disengagement of the first clutch leads to the completion of the disengagement of the first clutch CL1 at time t4, and the phase goes into the next phase. In this phase, after time t1 - time t3, with the engine idle speed Eng as the target engine speed, the engine speed control for the motor / generator MG is maintained in order to maintain the engine idle speed. Zero torque is maintained for the engine torque, and the electric motor torque is controlled as torque corresponding to the engine load. The adjustable torque CL1 and the actual torque CL1 are controlled so that the adjustable torque CL1 indicates zero at time t4, although the response of the actual torque CL1 is delayed relative to the adjustable torque CL1. Adjustable hydraulic pressure CL1 maintains hydraulic pressure during t3. The timer becomes zero during a little after time t3. A timer-based prohibition flag is reset when this timer indicates zero. However, in the first preferred embodiment, when such control (not shown) is performed in which the determination of the flag information that the engine does not completely burn out (a flag indicating that the engine is in a state of complete combustion is deactivated) during t3, prohibition flag = 1, and after time t3, the prohibition flag is maintained equal to 1.

[0069] Time t4 — Time t5 is phase (3) of the HEV → EV transition. When the disengagement of the first clutch CL1 is completed at time t4, the reduction in engine speed and the motor speed is controlled. Then at time t4, the zero revolution transition is completed, and the phase goes into the next phase.

In this phase, control passes from controlling the number of revolutions of the electric motor / generator MG from time t1 to time t4 to controlling the torque (command ONm) of the electric motor / generator MG, and during t5, the number of revolutions of the electric motor is reset. The engine speed is reset to zero before time t5 due to control in the engine fuel cut-off mode Eng. The engine torque provides negative torque due to control in the fuel cutoff mode, and the electric motor torque maintains zero torque, which is the target of torque control. The adjustable torque CL1 and the actual torque CL1 are maintained equal to zero, which represents the disengaged state of the first clutch CL1. Adjustable hydraulic pressure CL1 maintains hydraulic pressure during t4. The prohibition flag remains 1 based on such information that the Eng engine is not in a state of complete combustion. Then, after time t5, the vehicle is prepared for the vehicle to start moving in response to the operation of pressing the accelerator pedal in EV mode. In EV mode, after time t5 from the moment the vehicle is stopped. Thus, the number of revolutions is zero, and the determination of the stroke based on the magnitude of the variation in the torque MG cannot be performed (the revolutions do not vary, even if the clutch engages).

Therefore, the definition of the course is given as "prohibition".

[0070] When controlling the selection N → D, after switching to the EV mode, in order to prepare for the vehicle to start due to the operation of pressing the accelerator pedal, and to increase the response characteristic by starting by engaging the second brake B2 without delay in the response to hydraulic pressure , the override elimination control for the second brake B2 is performed. In this case, since the start times for eliminating the free play and the end for eliminating the free play are different, the following three patterns are provided (pattern (1), pattern (2) and pattern (3)), as shown in the hydraulic pressure control characteristics at the bottom of FIG. 8.

[0071] Template (1)

In the template (1), in which the times of the start of the removal of the free play and the end of the removal of the free play are before open-loop control (recognition prohibition), the control of the removal of the free play starts at t1, and the control of the removal of the free play ends (ends) during time t2, namely, the override elimination control is completed during the HEV mode. Consequently, normal N → D selection control and stroke recognition control are enabled, and the completion of the freewheel removal (determination of the start of engagement) is confirmed by setting the condition “torque variation magnitude MG> threshold value”, as shown by mark A with an arrow in FIG. 8.

[0072] Template (2)

In the template (2), in which the start time for eliminating the freewheeling is before open-loop control (recognition inhibit), but the completion time for eliminating the freewheeling is after open-loop control (inhibiting recognition), the override elimination control starts in time to time t2, and the freewheel removal control is completed during after time t2, namely, the mode switching control and the freewheel removal control partially overlap. Therefore, if the determination of the completion of the removal of the free play (determination of the start of engagement) is made by establishing such a condition that “the magnitude of the variation of the torque MG> threshold value”, there is a possibility of erroneous determination. Therefore, at time t2, the control changes from normal selection control N → D to open-loop control selection N → D, and control with stroke recognition is prohibited. Thus, erroneous determination of the determination of the start of engagement may not be allowed.

It should be noted that the determination of completion of the override elimination is performed by passing the time of the overrun timer TG, and the shaded region denoted by B in FIG. 8 is a part that has a higher pressure compared to controlled hydraulic pressure in conventional control.

[0073] Template (3)

In the template (3), in which the start time for eliminating the free play is after open-loop control (recognition prohibition), the removal of free play (control) starts during after time t2, and the removal of the free play (control) is completed during after time t3 namely, the mode switching control and the freewheel elimination control are mutually overlapping. Therefore, if the determination of the completion of the removal of the free play (determination of the start of engagement) is made by establishing such a condition that “the magnitude of the variation of the torque MG> threshold value”, there is a possibility of erroneous determination. Thus, at time t2, the control changes from normal N → D selection control to open-loop control by N → D selection, and stroke recognition control is prohibited. Therefore, an erroneous definition as determining the start of engagement may not be allowed. It should be noted that the determination of the completion of the removal of the free play is performed by passing the time of the timer TG of the removal of the free play, and the shaded area shown in C of FIG. 8 is a portion that is higher than the controlled hydraulic pressure in conventional operation.

[0074] Next, an advantage of the control device in the first embodiment is explained. The control device for automatic transmission AT in the first preferred embodiment has the following advantages.

[0075] (1) A control device for an AT automatic transmission into which driving forces from driving sources including an Eng engine and an electric motor (MG electric motor / generator) are input includes: a friction engagement member (second brake B2) engaged in the range of motion (D-range); means for determining the start of engagement (steps S2 → S3 → S4 in FIG. 6) for determining that the friction engagement element (second brake B2) has started engagement in case the load of the electric motor (motor / generator MG) increases by a predetermined amount during control of the number of revolutions at which the number of revolutions of the input shaft IN of the automatic transmission AT is controlled as a predetermined target number of revolutions, and when the range of motion is selected (selection N → D) to engage the friction element in clutch (second brake B2) in the disengaged state; and determination prohibiting means (steps S2 → S5 → S6 in FIG. 6) for prohibiting the determination by means of determining the start of engagement before determining that the friction engagement element (second brake B2) has started engagement, and in case there is a switch from the HEV mode, in which the driving forces of the engine Eng and the electric motor (MG motor / generator) are input to the input shaft IN, in the EV mode, in which only the driving force of the electric motor (motor / generator) is input to the input shaft IN.

Therefore, the erroneous determination of the load variation of the electric motor (electric motor / generator MG), which develops as a result of switching from the HEV mode to the EV mode, as the start of engagement of the friction engagement element (second brake B2), may not be allowed.

[0076] (2) The control device for AT automatic transmission further comprises: means for setting the hydraulic pressure during the inhibit (step S5 of FIG. 6) for setting the adjustable hydraulic pressure in the friction engagement element (second brake B2) to exceed the pressure in the case of non-prohibition in during a predetermined time interval (overrun timer TG), if the determination is prohibited by the determination inhibiting means (steps S2 → S5 → S6 in FIG. 6).

Therefore, in addition to the advantage described in (1), even if the start of engagement of the friction engagement element (second brake B2) cannot be determined from the magnitude of the load variation of the motor / generator MG, the state in which the elimination of the friction free play is completed can be guaranteed gearing element (second brake B2).

[0077] (3) In the control device for the AT automatic transmission, the detection inhibiting means (step S2 in FIG. 6, FIG. 7) prohibits the determination by the engagement start detection means (step S16 in FIG. 7) before determining that the engagement begins friction engagement element (second brake B2), and in the event that the engagement element (first clutch CL1), placed between the Eng engine and the electric motor (MG electric motor / generator), has started disengagement.

Therefore, in addition to the advantages (1) and (2), the determination of the start of engagement is prohibited when the engagement element (first clutch CL1) has started disengaging.

Thus, erroneous determination of the load variation of the electric motor / generator MG, which develops due to the switching of the mode from the HEV mode to the EV mode, as the start of engagement, may not be allowed.

In other words, when the mode switches from the HEV mode to the EV mode, the disengagement control of the engagement element (first clutch CL1) located between the Eng engine and the electric motor (MG electric motor / generator) starts. With this aspect in mind, determining the start of engagement according to the amount of variation in torque MG is prohibited.

Second Embodiment

[0078] In a second preferred embodiment, determining the start of engagement according to the magnitude of the variation in torque MG is prohibited if a phase transition signal from the HEV mode to the EV mode is detected.

[0079] First, the structure is explained.

Detailed structure of the prohibition flag setting process

FIG. 9 shows a flowchart representing a flowchart of a prohibition flag setting process performed in the AT controller 7 in the second preferred embodiment.

Each step in FIG. 9, representing a detailed structure of the prohibition flag setting process. It should be noted that since each step in relation to step S23 and steps S25-S28 corresponds to each step in relation to step S13 and steps S15-S18 in FIG. 7, their explanation is omitted herein.

[0080] In step S21, the AT controller 7 determines whether or not the previous phase signal value represents the HEV mode phase. If “Yes” (previous phase signal value = HEV mode phase), the procedure proceeds to step S22. If “No” (the previous value of the phase signal is the phase of the HEV mode), the procedure proceeds to step S24.

[0081] In step S22, the AT controller 7 determines whether or not the phase signal indicates the phase of the HEV → EV transition, after determining in step S21 that "the previous value of the phase signal = phase of the HEV mode".

If “Yes” (transition phase HEV → EV), the procedure proceeds to step S23. If “No” (not the transition phase HEV → EV), the procedure proceeds to step S24.

[0082] In step S24, after determining in step S21 that "the previous value of the phase signal is the HEV mode phase", then determining in step S22 that "is not in the transition phase, HEV mode → EV mode", or after setting the countdown timer in step S23, the AT controller 7 updates the previous phase signal value, and the procedure proceeds to step S25. It should be noted that the previous phase signal value is updated as “previous phase signal value = current phase signal value”.

It should be noted that another structure in the second preferred embodiment is identical to the structure of FIG. 1-6 in the first preferred embodiment, its explanation and designation in the drawings herein is omitted.

[0083] The flowchart of the second preferred embodiment is now explained.

The sequence of operations in the process of setting prohibition flags

As described above, when a mode switchover occurs from the HEV mode to the EV mode, the prohibition flag is set to 1 depending on a specific condition indicating that the mode is being switched. Further in this document, as a specific condition under which the mode is switched, the sequence of operations in the process of setting the prohibition flags in the second preferred embodiment is explained using the condition for determining the transition signal of the HEV mode phase to the EV mode.

[0084] If such conditions, "that the previous value of the phase signal = phase of the HEV mode", and that the "phase of the transition HEV → EV" are set in the flowchart of FIG. 9, the procedure is as follows: step S21 → step S22 → step S23 → step S24 → step S25 → step S26 → step S27 → step back. In step S23, the countdown timer is set as “timer value = predetermined value”. In step S26, after determining in step S25 that the "timer value> 0", the prohibition flag is set to 1, which represents the prohibition of determining the start of engagement.

[0085] Then, during the time interval from the time at which the subsequent control period begins, to the time at which the timer value becomes zero, in the flowchart of FIG. 9, the sequence of operations is repeated in the form of “step S21 → step S24 → step S25 → step S26 → step S27 → return”, and the prohibition flag = 1. In addition, when “timer value = 0”, in the flowchart 9, the process is repeated in the form of “step S21 → step S24 → step S25 → step S28 → return”. In step S28, after determining in step S25 that “the timer value = 0”, the prohibition flag is reset to 0 (prohibition flag = 0).

[0086] In the second embodiment, before determining that the engagement of the second brake B2 is started, and if a phase transition signal from the HEV mode to the EV mode is detected, the prohibition flag representing the prohibition of determining the engagement start is set to 1.

In other words, the mode switching from the HEV mode to the EV mode occurs based on the phase transition signal from the HEV mode to the EV mode. Thus, when a phase transition signal from the HEV mode to the EV mode is detected, the determination of the start of engagement is prohibited. Therefore, the erroneous determination of the load variation of the electric motor-generator, which develops due to the switching of the mode from the HEV mode to the EV mode, as the start of engagement, may not be allowed.

It should be noted that the rest of the sequence of operations of the second embodiment is identical to the first embodiment, and therefore, its explanation is omitted herein.

[0087] Next, an advantage is explained.

A control device for an AT automatic transmission in a second preferred embodiment provides the following advantage.

[0088] (4) The determination prohibition means described above (step S2 in FIG. 6, FIG. 9) prohibits the determination of the start of engagement by means of the determination (step S26 in FIG. 9) before determining that engagement of the friction engagement element (second brake B2 ), and if a phase transition signal is detected from the HEV mode to the EV mode.

Therefore, in addition to the advantages of (1) or (2) in the first preferred embodiment, when a phase transition signal from the HEV mode to the EV mode is detected, the determination of the start of engagement is prohibited. Thus, erroneous determination of the load variation of the electric motor / generator MG, which develops due to the switching of the mode from the HEV mode to the EV mode, as the start of engagement, may not be allowed. In other words, based on the phase transition signal from the HEV mode to the EV mode, a switchover occurs from the HEV mode to the EV mode. In light of this aspect, it is prohibited to determine the start of engagement according to the magnitude of the variation in torque MG.

Third Embodiment

[0089] In a third preferred embodiment, the determination of the start of engagement according to the magnitude of the variation in torque MG is prohibited if it is detected that the process of stopping the engine has started.

[0090] First, a structure in a third preferred embodiment is explained.

Detailed structure of the prohibition flag setting process

FIG. 10 shows a flowchart representing a flowchart of a prohibition flag setting process performed in the AT controller 7 in the third preferred embodiment. Each step in FIG. 10, representing a detailed structure of the prohibition flag setting process. It should be noted that since each step in relation to step S33 and steps S35-S38 corresponds to step S13 and steps S15-S18 in FIG. 7, their explanation is omitted herein.

[0091] In step S31, the AT controller 7 determines whether or not the previous value of the state of the engine is a state during driving due to the engine. If “Yes” (“previous value of the engine state = at the time of driving by the engine”), the procedure proceeds to step S32. If “No” (“previous value of the state of the engine ≠ during driving by the engine”), the procedure proceeds to step S34.

[0092] In step S32, the AT controller 7 determines whether or not the start signal of the engine stop process has been detected after determining in step S31 that “the previous value of the state of the engine = at the time of driving by the engine”. If “Yes” (detection of a signal to start the engine shutdown process), the procedure proceeds to step S33. If “No” (there is no detection of a signal to start the engine shutdown process), the procedure proceeds to step S34.

[0093] In step S34, after determining in step S31 that "the previous value of the state of the engine ≠ during driving by the engine", determining in step S32 that the signal to start the engine stop process is not detected, or the job in step S33 is a countdown timer, the previous engine state value is updated, and the procedure proceeds to step S35.

It should be noted here that the previous engine state value is updated as follows: previous engine state value = current engine state value.

Since other structures are identical to those of FIG. 1-6 in the first embodiment, their designation in the drawings and explanation in this document are omitted.

[0094] Next, a flowchart of a third preferred embodiment will be explained.

The sequence of operations in the process of setting prohibition flags

As described above, when a mode switch from the HEV mode to the EV mode occurs, the prohibition flag is set to 1 according to a specific condition indicating the occurrence of the mode switch. The following explains the sequence of operations in the process of setting the prohibition flags in the third preferred embodiment, using the condition for determining the signal of the start of the engine shutdown process as a specific condition representing a mode switch.

[0095] Based on the switching of the mode from the HEV mode to the EV mode, when the condition is set that "the previous value of the engine state = driving due to the engine" and "determining the signal for starting the engine stop process" in the flowchart the operations of the method of FIG. 10, the following sequence of operations is formed: step S31 → step S32 → step S33 → step S34 → step S35 → step S36 → step S36 → step S37 → return.

In step S33, the countdown timer is set to a predetermined value (“timer value = predetermined value”). In step S36, after determining in step S35 that the "timer value> 0", the prohibition flag is set to 1, which represents the prohibition of determining the start of engagement.

[0096] Then, until the timer value indicates 0 from the subsequent control period, in the flowchart of FIG. 10, the sequence of operations is repeated in the form of “step S31 → step S34 → step S35 → step S36 → step S37 → return”, and the prohibition flag = 1. In addition, when the timer value = 0, in the flowchart of FIG. . 10, the process is repeated in the form of “step S31 → step S34 → step S35 → step S38 → return”. In step S38, after determining in step S35 that the timer value = 0, the prohibition flag is reset to 0 (prohibition flag = 0).

[0097] In the third preferred embodiment, before determining that the second brake B2 has started engagement, and if a start signal of the engine stopping process is detected, the inhibit flag prohibiting the determination of the engagement start is set to 1 (inhibit flag = 1).

In other words, when the mode switches from HEV mode to EV mode, the Eng engine shutdown process begins. Therefore, when a start signal is detected for the engine stopping process, the determination of the start of engagement is prohibited. Thus, the erroneous determination of the load variation of the electric motor / generator MG, which occurs due to a change in the mode from the HEV mode to the EV mode, as the start of engagement, may not be allowed.

It should be noted that since the rest of the sequence of operations is identical to the first preferred embodiment, its explanation is omitted.

[0098] Next, an advantage is explained. The control device for automatic transmission AT in the third preferred embodiment has the following advantage.

[0099] (5) The detection inhibiting means (step S2 in FIG. 6, FIG. 10) prohibits (step S36 in FIG. 10) the determination by the means of determining the start of engagement before determining that the friction engaging element (second brake B2) has started engagement , and if it is detected that the engine Eng.

Therefore, in addition to the advantage (1) or (2), when it is detected that the engine stop process has started for the Eng engine, the determination of the start of engagement is prohibited. Thus, the erroneous determination of the load variation of the electric motor / generator MG, which occurs due to a change in the mode from the HEV mode to the EV mode, as the start of engagement, may not be allowed. In other words, when a mode change occurs from the HEV mode to the EV mode, the engine stop process Eng. With this aspect in mind, determining the start of engagement according to the amount of variation in torque MG is prohibited.

[0100] As described above, a control device for an automatic transmission according to the present invention is explained based on the first, second and third preferred embodiments. However, the specific structure is not limited to these preferred embodiments. Structural modifications and additions are permitted without departing from the essence of the invention associated with the corresponding claims.

[0101] In a first preferred embodiment, as a means of inhibiting determination, a determination of setting a prohibition flag based on an adjustable hydraulic pressure for the first clutch CL1 is illustrated. However, as a means of inhibiting determination, the actual hydraulic pressure of the first clutch CL1 is determined, and the setting of the inhibit flag can be determined based on the actual hydraulic pressure of the first clutch CL1.

[0102] In a third preferred embodiment, as a means of prohibiting determination, the prohibition flag is set to 1 (prohibition flag = 1) when a signal to start the engine shutdown process is detected. However, as a means of prohibiting determination, determining that the engine shutdown process for the engine starts may be based on when it is determined that the engine torque is reduced.

[0103] In the first, second, and third preferred embodiments, a normally closed type of a first clutch CL1 that is disengaged according to an increase in hydraulic pressure is illustrated as an engagement member disposed between the engine and the electric motor. However, as a gearing element located between the engine and the electric motor, a normally open first clutch can be used, which is disengaged by relieving the hydraulic pressure.

[0104] In the first, second and third preferred embodiments, the present invention is applicable to a hybrid vehicle that contains an electric SO / P oil pump, and an example is shown in which a mechanically-driven MO / P oil pump that is provided in the action through the input shaft of the automatic transmission is not actuated during the EV mode and the vehicle stops. However, the present invention is not limited to this. For example, in a vehicle in which an electric oil pump is not installed, and in which the number of revolutions of the input shaft is maintained equal to a constant number of revolutions by means of an electric motor driving the mechanical oil pump even in EV mode and when the vehicle is stopped, and the present invention is applicable to the transition from HEV mode to EV mode.

[0105] In the first, second and third preferred embodiments, as a timer for the prohibition flag, a sufficient duration is provided for a period of time from the time at which the engine shutdown process begins to the time at which the complete combustion flag n is deactivated (phase ( 1) transition HEV → EV). However, as a timer for the prohibition flag, the duration of the timer can be set to a timer duration such that stroke detection and stroke recognition control based on the magnitude of MG torque variation are prohibited when the mode is switched from HEV mode to EV mode.

[0106] In the first, second and third preferred embodiments, the automatic transmission control device according to the present invention is applied to a FR-type hybrid vehicle with one electric motor and two clutches. However, the control unit for automatic transmission is applicable to an FF hybrid vehicle with one electric motor and two clutches, or applicable to a hybrid vehicle of a different type than the one with one electric motor and two clutches, for example, to a parallel type hybrid vehicle, having a power flow separation mechanism. In general terms, the present invention is applicable to an electric vehicle in which an automatic transmission into which driving forces from driving sources including a motor and an electric motor are introduced is contained in a drive circuit.

Claims (8)

1. A control device for an automatic transmission, into which driving forces are input from sources of propulsion, including an engine and an electric motor, the control device comprising: - friction engagement element engaged in a range of motion; - means for determining the start of engagement to determine that the friction engagement element has started engagement if the electric motor load increases by a predetermined amount during the speed control at which the number of revolutions of the input shaft of the automatic transmission is controlled to a predetermined target speed, and when a range of motion is selected, and the friction engagement member in the disengaged state engages; and - a means of prohibiting determination to prohibit determining by means of determining the start of engagement before determining that the friction engagement element has started engagement, and in case there is a switch from the HEV mode, in which the driving forces from the engine and the electric motor are input to the input shaft, into the EV mode in which only the driving force of the electric motor is input to the input shaft. 2. The control device for automatic transmission according to claim 1, in which the means of prohibiting determination prohibits the determination by the means of determining the start of engagement before determining that the friction engagement element has engaged, and if the engagement element located between the engine and the electric motor has started disengaging. 3. The control device for automatic transmission according to claim 1, wherein the means of prohibiting determination prohibits determination by means of determining the start of engagement before determining that the friction engagement element has started engagement, and if a phase transition signal from the HEV mode to the EV mode is detected . 4. The control device for automatic transmission according to claim 1, in which the means of prohibiting determination prohibits the determination by means of determining the start of engagement before determining that the friction engagement element has started engagement, and if it has been detected that the engine shutdown process has started. 5. The control device for automatic transmission according to any one of the preceding paragraphs. 1-4, in which the control device further comprises: means for setting the hydraulic pressure during the prohibition to set the adjustable hydraulic pressure for the friction engagement element equal to the adjustable hydraulic pressure, which is higher than the pressure in the case of non-prohibition for a predetermined time interval in case the determination is prohibited means of prohibition of determination.

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